The role of a bacteriophage lysin in the supplementation of microbiome therapy to treat C. difficile infections.

Asnha looking at lab equipment.




Assistant Professor of Microbiology

Project Summary

­As a member of Michael Abt’s lab, I spent the summer working on potential mechanisms that could effectively treat and reduce the impact of C. difficile. C. difficile is a gram-positive spore forming bacteria that disrupts intestinal microbiota. It is the cause of over half a million infections per year and causes $4.8 billion dollars’ worth of damage.

 C. difficile infections are the result of excessive antibiotic treatments leading to loss of intestinal colonization resistance. Current first-line therapies involve the use of more antibiotics, notably metronidazole or vancomycin. Up to 35% of patients relapse with this treatment. Recently, a novel therapy, fecal microbiota transplant, has been implemented for recurrent cases, but up to 20% of patients fail to respond to treatment. I used an in vitro model to test the efficacy of a bacteriophage lysin, PlyCD1-174, (known to effectively treat C. difficile) in combination with a dehydroxylating gut bacteria called C. scindens in an in-vitro model to inhibit C. difficile growth.

Using bacterial plating techniques, I was able to grow samples of C. difficile and C. scindens in their respective media. The project allowed me to design my own protocol and experiment with different concentration of bacteria and lysin to optimize the inhibitory effect using their OD600 readings. Since I had worked in the Abt lab previously, I had exposure to techniques like qPCR, PCR and DNA isolation using power-soil kits. However, my research familiarized me with the workings of the anaerobic chamber, from replacing its components to trouble shooting fluctuating oxygen levels.

In addition to the techniques I learnt, I was introduced to the public health impact of microbiology research as well as current research in the field. The research papers I read enabled me to create my own hypothesis and test it. My experience at the Abt lab is invaluable as it prepares me for a future career in medicine. As a biology major, research is my passion and this summer research experience helps me consider the broader implications of work in labs.